LTE signal fingerprinting localization based on CSI

This paper investigates the possibility to use Channel State Information (CSI) extracted from Long Term Evolution (LTE) signals for signal fingerprinting localization. Being the first work in this direction, several types of signal fingerprinting-based approaches have been compared (e.g., CSI-based vs RSSI-based, statistic vs deterministic matching rule). In particular, the paper proposes a novel CSI-based signal fingerprinting that uses as fingerprint not directly the vector of channel gains per subcarrier, but rather some features extracted from these vectors. This method would greatly reduce the memory requirement of the database as well as the computational complexity of the matching phase. Experimental results, shown for both indoor and outdoor environments, confirm the effectiveness of the proposed method and also provide interesting insights on the use of LTE signal fingerprinting based on CSI.